The Striking Relationship Between Gun Safety Laws and Firearm Deaths

The research is now clear that states with stricter gun control measures have fewer gun-related fatalities.

Just this morning, the Senate Judiciary Committee approved a bill that would make it a federal crime to traffic guns (one of four gun control bills being discussed by the committee). This comes on the heels of an important new study published in JAMA Internal Medicine that documents the strong connection between stricter gun control laws and lower rates of gun deaths at the state level.

The study, by researchers at Boston Children's Hospital, Harvard Medical School, and Harvard School of Public Health, uses a measure of state-by-state "legislative strength" of gun control policies tracked by the Brady Center to Prevent Gun Violence, including measures to: (1) curb firearm trafficking; (2) strengthen background checks on purchasers of firearms beyond those required by the Brady Handgun Violence Prevention Act; (3) ensure child safety; (4) ban military style assault weapons; and (5) restrict guns in public places. It conducted a detailed statistical analysis (via a clustered Poisson regression) to examine the effect gun control laws on firearms fatalities.

The study found that states with the strictest gun control laws had lower rates of gun-related homicides and suicides, though it notes that these findings are limited to associations and could not determine precise cause-and-effect. Gun-related deaths were measured per 100,000 people for both homicides and suicides based on data from the Centers for Disease Control and Prevention, controlling for other factors thought to be associated with gun deaths including age, sex, race and ethnicity, poverty, unemployment, college education, population density, other violence-related deaths, and firearm ownership.

The map below, from the study, charts the mortality rate per 100,000 and legislative strength score. Louisiana had the highest rate of gun-related fatalities at 17.9 per 100,000, and Hawaii had the lowest at 2.9. Utah had the lowest legislative strength score of 0 and Massachusetts had the highest at 24.

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The three scattergraphs below show the correlation between these data, legislative strength score to firearm deaths and ownership, as well as firearm deaths to firearm ownership.

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For the statisticians among you, here is how the study summarizes its main conclusions:

This detailed study is in line with my own correlation analysis (done with my colleague Charlotta Mellander) in The Atlantic, where I note, "Firearm deaths are significantly lower in states with stricter gun control legislation. Though the sample sizes are small, we find substantial negative correlations between firearm deaths and states that ban assault weapons (-.45), require trigger locks (-.42), and mandate safe storage requirements for guns (-.48)."

Cities contributor John Roman, a senior fellow in the Justice Policy Center at the Urban Institute, says via email that this study is "a very important addition" to our understanding of the connection between gun control and gun violence. "In addition to the general relationship between gun safety laws and firearm deaths, the paper also suggests that increasing the number of gun safety laws increases the reductions in firearm related deaths. So the benefits just get bigger with more laws. The authors also identify background checks as the most important type of law." And while gun rights groups have already come out in force to criticize the study's methods and lack of cause and effect conclusions, he adds that "the authors are very careful in specifying their models and have done as rigorous a paper as possible with existing data."

The bottom line: gun control appears to work.

About the Author

Richard Florida is a co-founder and editor at large of CityLab and a senior editor at The Atlantic. He is a university professor in the University of Toronto’s School of Cities and Rotman School of Management, and a distinguished fellow at New York University’s Schack Institute of Real Estate and visiting fellow at Florida International University.